Modem RC7611 cannot connect in the ATT carrier

IoT Modules RC76
1

I have a problem with the GPRS modem RC7611 of Sierra Wireless, it initialize correctly, finding the sim card and respond the AT commands, but when it will connect in the carrier, it receive a denied status:

AT+CGMM

RC7611

OK

AT+KCELL=0

37,8,4,6,5035,184,36,9

OK

AT+CREG=0

OK

AT+CMEE=1

OK

AT+KPATTERN=“EOF”

OK

AT+KURCCFG=“TCP”,1,0

OK

AT+CTZU=1

OK

AT+CLCK=“SC”,2

OK

AT+CPIN?

OK

AT+CCID

+CLCK: 0

OK

AT+CCID

+CPIN: READY

OK

AT+CCID

+CCID: 89011703278703002751

OK

AT+COPS=0,2

OK

AT+CREG?

+CREG: 0,3

OK

AT+CREG?

+CREG: 0,3

OK

I have already verified the firmware version, the carrier preference and both are alright:

AT+CGMR

SWI9X07H_00.09.10.00 85890e jenkins 2023/09/25 03:16:56

OK

AT!IMAGE?

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
FW 1 EMPTY 0 0 0
FW 2 EMPTY 0 0 0
FW 3 EMPTY 0 0 0
Max FW images: 1
Active FW image is at slot 255

TYPE SLOT STATUS LRU FAILURES UNIQUE_ID BUILD_ID
PRI FF GOOD 0 00 001.096_000 00.09.10.00_ATT
PRI FF GOOD 0 00 001.094_000 00.08.20.00_GENERIC
PRI FF GOOD 0 00 001.050_000 00.08.20.00_TMO
PRI FF GOOD 0 00 001.066_000 00.08.20.00_VERIZON
Max PRI images: 50

OK

AT!IMPREF?

!IMPREF:
preferred fw version: 00.09.10.00
preferred carrier name: ATT
preferred config name: ATT_001.096_000
preferred subpri index: 001
current fw version: 00.09.10.00
current carrier name: ATT
current config name: ATT_001.096_000
current subpri index: 001

OK

Someone can help me with this issue ?

2

what is the return of AT!UIMS?
Is your SIM card OK to connect to AT&T?
Have you checked the APN in AT+CGDCONT? and see if it has been set correctly to your SIM card?

3

Thanks for your help, I’m testing here and I’ll tell you the answer to the test.

4

So I think there is no problem with the SIM card, as I received the CCID, so the modem is selecting the right SIM card and regarding the APN I couldn’t even access the operator, so I think I’m not at that stage yet, I wanted to know what could be giving this denied status in the CREG.

5

Have you put the sim card to a phone to verify

6

In my cellphone is working and I can access the internet.

7

then have you checked the APN used in the phone?

8

yes, in my phone is the NXTGENPHONE.

9

then what is the APN it is using in the phone for your AT&T SIM card?

10

In my phone:

APN NXTGENPHONE
MMSC http://mmsc.mobile.att.net
MMS proxy proxy.mobile.att.net

11

The APN that is used in my IOT module is this:

image

12

Have you checked the APN in AT+CGDCONT? in your RC7611 module then?

13

No, because the modem didn’t even reach the APN part, it can’t even register with the carrier with the CREG, shouldn’t the APN come later to be able to access the internet?

14

if you set the APN wrongly in your RC7611 module, can it register network?

you can do the experiment in your phone to set the same APN as RC7611

15

but is this to register with the carrier?
I thought APN was a proxy

16

probably you need to do the experiment to verify